In the United States Supreme Court case of The United States v. Jose Antonio Alviso, the issue was whether a Mexican citizen who had been living in California since 1822 and had become a naturalized citizen of Mexico in 1844 could be considered an alien under U.S. law and thus subject to deportation from the country. The court held that Alviso was not an alien because he had resided continuously within what is now part of the United States since before it became part of this nation, even though he later obtained citizenship elsewhere while still residing here. This decision established that those who were present when land became part of the U.S., regardless if they have taken on another nationality or not, are protected by our laws as citizens with all rights associated with such status including protection against removal from their homes without due process or just cause for doing so

In the case of United States v. Jose Antonio Alviso, the Supreme Court was asked to decide whether or not a Mexican citizen who had resided in California since 1846 and married an American woman could be considered a "citizen of the United States." The majority opinion held that he could not because he had never been naturalized under U.S. law, but Justice Grier dissented from this ruling on two grounds: firstly, that Congress did not have authority to pass laws concerning citizenship for those living in territories acquired by treaty; and secondly, that even if it did have such authority, there were no laws at the time which would allow Alviso to become a citizen without being naturalized. He argued further that as long as Alviso remained loyal to his adopted country and its government then he should be granted full rights of citizenship regardless of any formal process or paperwork required by law.